Discovery 2 TD5 fuel consumption question

lynall said:

Free always wins, think I ran my td5 on 10/40 syn, as it was free, did 50k in that machine.

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Exactly my friend , well it’s high quality oil we run it in all our fleet at work, so why not ‍ Arh yea what was she like ok start up on that stuff? Fair enough I’ve so far done 22,000 all on that 0/40 and I quite the stuff seems to clean it when it drains aswell

Let's hope neither of you'll get a big barrel of sunflower oil for free then

IF... it's the free oil, have you worked out yet how much it has cost you in excess fuel use?

yfo866 said:

IF... it's the free oil, have you worked out yet how much it has cost you in excess fuel use?

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Doubt it will kae a measureable difference?

feelingaliveintheTD5 said:

Exactly my friend , well it’s high quality oil we run it in all our fleet at work, so why not ‍ Arh yea what was she like ok start up on that stuff? Fair enough I’ve so far done 22,000 all on that 0/40 and I quite the stuff seems to clean it when it drains aswell

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Was a few years ago now, I liked that car a lot.
As for starting I dont remember any issues, it just worked, and i think its still on the road.
Sold it in 2008 with 106k on the clock

lynall said:

Doubt it will kae a measureable difference?

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Consumption down from 32mpg to 24mpg?
I think even Diane Abbott could measure that

yfo866 said:

Consumption down from 32mpg to 24mpg?
I think even Diane Abbott could measure that

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We all know its not the oil, I bet you a pint if you ran a td5 on the thickest engine oil you could buy the mpg would not be massively different, the engine would of course not be happy.
As for abbott, dont bet on it

From memory I think there is a post very much along the same lines as this one every few months, always seems to be the td5 model as well.

yfo866 said:

IF... it's the free oil, have you worked out yet how much it has cost you in excess fuel use?

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?? Are you suggesting it’s using that oil that’s caused the drop in fuel economy because I ran it on that oil for 7 months and it was fine at the time doing 31-32 mpg before I noticed it drinking fuel?

lynall said:

We all know its not the oil, I bet you a pint if you ran a td5 on the thickest engine oil you could buy the mpg would not be massively different, the engine would of course not be happy.
As for abbott, dont bet on it

From memory I think there is a post very much along the same lines as this one every few months, always seems to be the td5 model as well.

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lynall said:

We all know its not the oil, I bet you a pint if you ran a td5 on the thickest engine oil you could buy the mpg would not be massively different, the engine would of course not be happy.
As for abbott, dont bet on it

From memory I think there is a post very much along the same lines as this one every few months, always seems to be the td5 model as well.

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Yes I do have to agree I don’t believe it’s the oil that’s caused this as it ran on it for around 6-7 months before hand on that 0w-40 doing 31-32 mpg

You haven't got a fuel leak have you?

feelingaliveintheTD5 said:

Yes I do have to agree I don’t believe it’s the oil that’s caused this as it ran on it for around 6-7 months before hand on that 0w-40 doing 31-32 mpg

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I ran that manual td5 (on 10/40 oil) for 50k, and dont think I ever once got 30mpg, 25/28 was the norm, mainly commuting 12 miles each way, some biggish hills on the route.

Shimsteriom said:

You haven't got a fuel leak have you?

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Unfortunately not, I’ve been through checked all the lines checked for any moisture or dampness and even pressure tested the head!! Yes it was professional but still proved it held pressure.

feelingaliveintheTD5 said:

Unfortunately not, I’ve been through checked all the lines checked for any moisture or dampness and even pressure tested the head!! Yes it was professional but still proved it held pressure.

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Still good power?
Egr working as it should, or blanked?

lynall said:

Still good power?
Egr working as it should, or blanked?

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Yea she pulls well I thinks, especially for her age, EGR has been blanked first thing I did when I brought it like within a week

feelingaliveintheTD5 said:

Yea she pulls well I thinks, especially for her age, EGR has been blanked first thing I did when I brought it like within a week

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MAP sensor worth a look, its bolted into the inlet manifold, you can find the specs on the web and check yours with a multimeter.
Mine went flat power wise and it was the map sensor that had died, yours may not be dead, but maybe ill?

Also an issue on the D3, not dying, but the sensor hole blocking up with egr gunge.

lynall said:

MAP sensor worth a look, its bolted into the inlet manifold, you can find the specs on the web and check yours with a multimeter.
Mine went flat power wise and it was the map sensor that had died, yours may not be dead, but maybe ill?

Also an issue on the D3, not dying, but the sensor hole blocking up with egr gunge.

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I like the thinking but I’ve already swapped it with another one from a friends disco MAP is also reading ok on the snappy box however I have yet to test it like resistance etc but the reading is correct

Could it be a stuck open thermostat causing the engine to take longer to warm up?
Or a boost pipe leak causing over fuelling compared to reduced air into the engine?
When the fuel temp sensor failed on my Ibiza TDi, that caused a drop in fuel economy. Do TD5 engines have one of these?

lynall said:

MAP sensor worth a look, its bolted into the inlet manifold, you can find the specs on the web and check yours with a multimeter.

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There are no values to check with multimeter on a MAP/IAT sensor unless it's open or short circuit but then it would cause more trouble than just consumption

sierrafery said:

There are no values to check with multimeter on a MAP/IAT sensor unless it's open or short circuit but then it would cause more trouble than just consumption

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Yes there is, I did it years ago.
It was how I knew mine was out of spec, you measured resisstance values/volts at certain temps, info was on the web from a LR document, a search might find it?
This was back in the days of the discovery owners club.

Some weird stuff went wrong with that td5, throttle tracks wore out causing a signal mismatch, the MAP, though never any issues with the MAF, inj loom, other elec issues I have most likely forgotten, safe to say it had a constant to do list like all my previous LRs.